| Mechanical Specification General
Exposed metal surfaces shall be painted with an air-dry beige direct to metal
single component paint prior to shipment. Each unit
shall ship with a full operating charge of refrigerant
and oil. Molded neoprene isolation pads shall be supplied for placement under all support points. Start-up and operator
instruction by factory-trained service personnel shall
be included.
Compressor-Motor
The unit shall have a semihermetic, direct-drive, 3600 rpm (3000 rpm 50
Hz), rotary compressor with: capacity control slide
valve, oil sump heater and differential pressure
refrigerant oil flow system. Four pressure lubricated rolling element bearing
groups shall support the rotating assembly. Motor shall be a suction gas-cooled, hermetically sealed, two-pole, squirrel cage
induction-type.
Evaporator-Condenser
Shells shall be carbon steel plate. Evaporator and condenser shall be designed,
tested and stamped in accordance with ASME Code for
refrigerant side working side pressure of 200 psig.
All tube sheets shall be carbon steel. Evaporator and condenser tubes should
be individually replaceable. Standard tubes shall be
externally finned, internally enhanced seamless copper with lands at all tube sheets. Evaporator tubes shall be 1.0-inch diameter.
Condenser tubes shall be 3 /4- -inch diameter. Tubes
shall be mechanically expanded into tube sheets. Condenser and evaporator tubes
shall be mechanically fastened to tube supports.
All water pass arrangements shall be available with grooved connections (150 or 300 psig waterside). All connections
may be either right or left handed. Waterside shall be
hydrostatically tested at 1 1 /2 times design working pressure.
Refrigerant Circuit
An electronically controlled expansion valve shall be provided to maintain proper refrigerant flow.
Unit Control Panel
(UCP2 ™ )
The microprocessor-based control panel shall be factory-installed and tested. The control system shall be powered by
a control power transformer. The controller will load
and unload the chiller via control of the compressor slide valve. Microprocessor
based chilled water reset based on return water shall
be standard.
The UCP2 utilizing the Adaptive Control ™ microprocessor automatically shall
take action to prevent unit shutdown due to abnormal
operating conditions associated with low evaporator refrigerant temperature, high condensing temperature, and motor current
overload. If the abnormal operating condition continues
and the protective limit is reached, the machine
will be shut down.
The panel shall include machine protection shutdown requiring manual reset
for:
- low evaporator refrigerant temperature and pressure
- high condenser refrigerant pressure
- low oil flow
- critical sensor or detection circuit faults
- motor current overload
- high compressor discharge temperature
- communications lost between modules
- electrical distribution faults: phase loss, phase imbalance, phase reversal
- external and local emergency stop
- starter transition failure
The panel shall include machine protection shutdown with automatic reset when
the condition is corrected for:
- momentary power loss
- under/overvoltage
- loss of evaporator or condenser water flow
Over 100 diagnostic checks shall be made and displayed when a fault is detected. The display shall indicate the fault,
the type of reset required, the time and date the
diagnostic occurred, the mode in which the machine was
operating at the time of the diagnostic, and a help message. A diagnostic history
shall display the last 20 diagnostics with the time and
date of their occurrence. |
